Medical overtreatment has caused a lot of waste of medical resources. In the face of the increasingly serious medical overtreatment phenomenon, it is of great significance to clarify the factors of medical overtreatment to help solve this problem in China. In this study, we use the medical overtreatment text as a corpus and use latent Dirichlet allocation (LDA) topic model for topic extraction. Based on the extracted topics, a path model is established and the structural equation model(SEM) is used to test the path model. Finally, the influence factors of medical overtreatment are obtained. The results show that this study has extracted three main reasons that affect medical overtreatment, namely doctors, hospitals and patients. The factors influencing doctors' medical overtreatment are the institutions, benefits, and induced demand. The factors that affect patients' overtreatment are health and medical insurance. The factors that influence hospitals' medical overtreatment are monopoly, economics, and management. These factors significantly affect the occurrence of medical overtreatment. Therefore, public health organizations should proceed from these three aspects and formulate effective measures to solve the problem of medical overtreatment.